Sna is probably the busiest commercial airport I've flown to. Arrival was uneventful after a 2 hour flight. The trip was to attend a funeral, with return the same night. I was tired. Problems with clearance delivery and taxiing at night at an unfamiliar airport left me somewhat flustered. During run-up I neglected to verify HSI heading correctness, and didn't set back-up copilot directional gyro. After takeoff, an ATC vector made me realize something was wrong, but I didn't know what. I told ATC I had a gyro problem and needed to figure it out. I had been cleared to 2000 ft, but climbed to 2500 ft to be above the stratus for VFR conditions. Due to confusion with HSI and misset directional gyro, I was not holding heading. ATC agreed to let me stay at 2500 ft and gave me leeway to solve the problem. Factors: fatigue, flustered by busy airport, didn't follow run-up checklist, HSI invalid flag very poorly designed and hard to see at night. Could have used GPS for heading, but it was hard to think of more than 'fly the plane' due to stress. Eventually figured everything out and continued without problem.

Narrative: SNA IS PROBABLY THE BUSIEST COMMERCIAL ARPT I'VE FLOWN TO. ARR WAS UNEVENTFUL AFTER A 2 HR FLT. THE TRIP WAS TO ATTEND A FUNERAL, WITH RETURN THE SAME NIGHT. I WAS TIRED. PROBS WITH CLRNC DELIVERY AND TAXIING AT NIGHT AT AN UNFAMILIAR ARPT LEFT ME SOMEWHAT FLUSTERED. DURING RUN-UP I NEGLECTED TO VERIFY HSI HDG CORRECTNESS, AND DIDN'T SET BACK-UP COPLT DIRECTIONAL GYRO. AFTER TKOF, AN ATC VECTOR MADE ME REALIZE SOMETHING WAS WRONG, BUT I DIDN'T KNOW WHAT. I TOLD ATC I HAD A GYRO PROB AND NEEDED TO FIGURE IT OUT. I HAD BEEN CLRED TO 2000 FT, BUT CLBED TO 2500 FT TO BE ABOVE THE STRATUS FOR VFR CONDITIONS. DUE TO CONFUSION WITH HSI AND MISSET DIRECTIONAL GYRO, I WAS NOT HOLDING HDG. ATC AGREED TO LET ME STAY AT 2500 FT AND GAVE ME LEEWAY TO SOLVE THE PROB. FACTORS: FATIGUE, FLUSTERED BY BUSY ARPT, DIDN'T FOLLOW RUN-UP CHKLIST, HSI INVALID FLAG VERY POORLY DESIGNED AND HARD TO SEE AT NIGHT. COULD HAVE USED GPS FOR HDG, BUT IT WAS HARD TO THINK OF MORE THAN 'FLY THE PLANE' DUE TO STRESS. EVENTUALLY FIGURED EVERYTHING OUT AND CONTINUED WITHOUT PROB.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.